Process for flotation of cassiterite



form a soft froth, which will contain the Patented Dec. 3, 1929 UNITEDSTATES PATENT OFFICE ROYAL S. HANDY, OF KELLOGG; IDAHO, AND RAYMOND IR.BEARD, 0F LALLAGUA,

BOLIVIA, ASSIGNOIRS TO PATINO MINES 8c ENTERPRISES CONSOLIDATED INQ, OFNEW YORK. N. Y., A. CORPORATION OF DELAWARE PROCESS FOR FLOTATION 0FGASSITERITE No Drawing. Application filed November 13, 1928, Serial No.319,181,

This invention relates to the concentration of ores by flotation methodsand it is particularly adapted for use in connection with orescontaining cassiterite.

It is Well known that the usual flotation methods that are used for theseparation of 'metalliferous particles from ores, such as copper ores,are not applicable to the treatment of ores containing cassiterite, forthe reason that cassiterite is extremely resistant to flotation.

The present invention, however, is particularly adapted for thetreatment of ores containing cassiterite, for by this method thecassiterite can be floated and recovered in the usual way. This methodhas been successfully used on a commercial scale in the treatment ofores at the mill of the Patino Mines & Enterprises Consolidated, Inc, atLallagua, Bolivia.

In our improved process the material to be treated is convenientlyground by any of the well-known methods and mixed with water to form apulp which may be heated if necessary. To this pulp is then added analkaline electrolyte, such as carbonate of sodium, hydrate of sodium orother alkali; a substance, such as sulphate of copper or other acidsalt, to put it in condition; a collector or athering material which maybe a saponifiable substance, such as oleic acid or other grease acid;and a deflocculator, such as silicate of sodium or other gelatinoussubstance. The mixture is then violently agitated and subjected toaeration to give it enough air to cassiterite which is the mineral to berecovered. The froth is separated by any well known method and can beretreated againin like manner in order to increase the percentage ofcassiterite in the froth.

If the froth contains pyrites or other sulphides it can be treated againin the same manner with sulfuric acid or an acid electrolyte, to causethe sulphides to float in the resulting froth without the flotationofthe cassiterite, and thus effect a separation of the cassiterite andsulphides.

The following are typical examples of our new process:

and in Bolivia December 5, 1927.

Ewample 1.-1000 grams of pulp taken from a Dorr classifier at the PatinoMines were wellagitated in a flotation machine together with 5. grams ofcarbonate of sodium, 2 grams of sulphate of copper, 10 grams of Sun oilNo. L. B. and 5 c. c. of commercially pure silicate of sodium. Uponagitation with the admission of air a creamy froth of even compositioncontaining pyrites, cassiterite and silicate material raised to thesurface and was removed. Upon further treatment this froth was found tocontain 76% of the tin contained in the material treated.

Ewample Q.1000 grams of material taken from the above-mentioned plantwas mixed with water and ground in a ball mill using steel balls to asize for flotation-together with 2 grams of sulphate of coper, 5 gramsof carbonate of sodium, 5 c. c. of commercially pure silicate of sodiumand 4 drops of Barrett oil No. 4. This pulp was then agitated in aflotation machine with 1 c. c. of oleic acid. Air was then admitted andthe froth collected. This froth contained 92% of the tin contained inthe material treated, having an assay of 16.5% Sn.

Ewample 51-1000 grams of pulp from a Dorr classifier were agitated whilein a flotation machine together with 5 grams of sodium carbonate, 2grams of copper sulphate, 10 grams of sodium silicate and 5 grams ofsoft soap. Air was admitted'during the agita tion and a creamy frothraised to the surface carrying with it a major part of the cassiteritecontained in the pulp treated, as was 'determined by washing in a platethe tailings from the machine. The froth was taken and put again in aflotation machine without the addition of any more of the reagents. Thefroth recovered therefrom contained 17.5% Sn. while the pulp treatedcontained 4.4% Sn.

What we claim is 1. The ing cassiterite which consists in mixing the orein a finely divided condition with water so as to form a pulp,subjecting the pulp to agitation in the presence of an alkalineelectrolyte, an acid salt, a saponifiable substance and a deflocculator,supplying the pulp while being agitated with air to forma froth withrocess for treating ores contain- 'to form a pulp, heating the pulp,

the cassiterite floating therein, removin the froth, and separating thecassiterite t erefrom.

2. The process for treating ores containing cassiterite which consistsin mixing the ore in a finely divided condition'with water so assubjecting the pulp to agitation in the presence of an alkalineelectrolyte, an acid salt, a saponifi-.

able substance and a deflocculator, supplying the pulp while beingagitated with air to form a frothwith the cassiterite. floating therein,removing the froth,-and separating I o the cassiterite therefrom.

ores containing 3. The process'of treating grinding the ore cassiteritewhich consists in to a finely divided condition, mixing it with phate,oleic acid,'and silicate of so water to form a pulp, agitating the pulpin the presence of small portions of sodium carbonate, copper sulphate,saponifiable ease and silicate of SOdlllIIl, aerating the mlxture duringagitation -to form a froth with the cassiterite floating therein, andremoving the 'froth. p I 4. The process of treating ores containingcassiterite which consists in mixing the ore in a finely dividedcondition with water to form a'pulp, adding to the pulp an alkalineelectrolyte, an acid salt, a saponifiable substance, and adeflocculator, a 'tating the pulp and admitting air thereto iii-incollecting the resulting froth, a ding water and anacid to said frothand agitating the same to effect a separation of the sulphides andcassiterite, then removing said sulphides, and collecting thecassiterite.

5. The process of treating ores containing cassiterite which consists inmixing the ore in a finely divided condition with water to form a fpulp,adding to the pulp small portions 0 carbonate of sodium co per sulium,agitating the pulp and admitting air thereto during a itation,collecting the resulting froth, ad ing water and an acid electrotlfyteto said froth and agitating the same to e ect a separation of thesulphides and cassiterite, then removing said sulphides, and collectingthe cassiterite.

This specification signed this 27th day'of August, 1928.- a v ROYAL S.HANDY. This specification signed this 17 day of October, 1928.

V RAYMOND R. BEARD.

agitation,

